Journalists Get Schooled on the Microbiome

Guest BloggerMicrobiome Environment, Uncategorized


The popular press has discovered probiotics.

Barely a week goes by when a provocative story doesn’t herald the ups and downs of microbiome research. Often these headlines feel like a wild ride on a roller coaster when the science is actually far less dramatic.

For example, two recent studies published in the September 6th issue of Cell by scientists at the Weitzman Institute of Science in Israel garnered widespread media coverage due to negative conclusions on probiotics. With news headlines like “Probiotics Not Always Useful” the usual optimism for effects of probiotics was challenged.

IPA’s Executive Director George Paraskevakos released a statement soon after the maelstrom: “Clearly, some press is not taking the time to tease apart these findings and report within an accurate context. For example, the study appears to confuse colonization with efficacy. They also don’t appear to be looking at the more than 1,200 studies showing probiotic benefits.”

Just as scientific journals should be more stringent in publishing (“publish or perish” protocols can make strivers in academia desperate), journalists too shoulder some of the responsibility in taming down the rhetoric.

To that end, Daniel McDonald offered up some pointers to his fellow journalists in a blog for the Annenberg Center for Health Journalism at University of Southern California. Journalists don’t just follow your gut when covering the microbiome was published November 14, 2018. The article provides guidelines for anyone writing in the microbiome space.

McDonald begins with a brief introduction on why these organisms have become an intense area of research. He explains how new techniques such as DNA sequencing opened wide the opportunity to link microbiomes with disease. Those associations while exciting for their potential in human health also offer cautionary tales.

First lesson: correlation is not causation

“The microbiome field is full of correlative or associative stories, and it’s easy for journalists to fall into the trap of mistaking correlation for causation when reporting on exciting research findings,” wrote McDonald. He used studies from his employer American Gut Project based at the University of California, San Diego’s School of Medicine as examples.

Studies that demonstrate causation are uncommon in the microbiome field. In addition, McDonald noted, mice and humans differ, particularly in their immune systems, therefore it’s not safe to extrapolate the results to humans .

Second lesson: questions every journalist should ask when reporting on research

  • Are claims supported by peer-reviewed research?
  • Do the research authors have any conflicts of interest?
  • Is the study design valid? Know the difference between cross-sectional, longitudinal and the gold standard which are double-blind randomized controlled trials.
  • Sample size must always be considered with fewer numbers nearly always less desirable.

Third lesson: Get a second opinion

Another way for journalists to get to the truth is to interview the authors of the study. A contact email address is usually given in the list of researchers. Also recommended is talking with a researcher not involved in the study for his or her take. Groups like the Center for Microbiome Innovation at UC San Diego may be able to suggest researchers to contact.

“Remember, it’s always smart to be skeptical about language that implies causation or cures. When in doubt, be sure to follow up with a microbiome scientist unaffiliated with the study under discussion for a second opinion.” –Daniel McDonald

Remember: A second opinion never hurt anyone and can go a long way at uncovering the truth.